Wasp vs hornet vs yellow jacket: an Iowa identification guide

All three sting. All three live in Iowa. Knowing which one you have changes how dangerous the nest is and how it should be removed.

Iowa homeowners use 'wasp,' 'hornet,' and 'yellow jacket' interchangeably, and most of the time it doesn't matter — until it does. The species changes the aggression level, the nest location, and the right removal approach.

Paper wasps

Long, slender, brownish with yellow or red markings. They build the open, umbrella-shaped paper nest you see hanging under eaves, deck railings, and grill lids. Colonies are small (usually under 100 wasps). Paper wasps will defend a nest but are not generally aggressive away from it. Most Iowa homeowners can manage a small, accessible paper wasp nest safely with a knockdown spray at dusk.

Bald-faced hornets

Black with a white face and white markings on the abdomen. They build the gray, football-shaped enclosed paper nest you see hanging from tree branches, under soffits, or attached to siding — sometimes the size of a basketball by August. Colonies can hit 400+ workers and are extremely defensive. Do not approach a bald-faced hornet nest. They can sting repeatedly and will pursue you 50+ feet from the nest.

Yellow jackets

Short, stocky, bright yellow and black, often confused with bees. Yellow jackets nest in the ground (old rodent burrows are favorites), inside wall voids, and in landscaping. By late summer an Iowa yellow jacket nest can have 1,000–4,000 workers. They are the most aggressive stinging insect in Iowa and the species responsible for most stings in late summer and fall.

What to call a pro for

• Any bald-faced hornet nest, regardless of size.
• Any nest inside a wall, soffit, attic, or chimney.
• Yellow jacket nests in the ground when they're near walkways or play areas.
• Any nest you can't reach safely from the ground.
• Anyone in the household with a known sting allergy.

Iowa season

Wasp activity in Iowa starts in May (queens building) and peaks in August and September when colonies are at maximum size and food is getting scarce. Late summer is when stinging incidents spike — that's when yellow jackets show up at your picnic.